Final answer:
The hepatic diverticulum and foregut narrow to form the bile duct system, leading to the transport of bile from the liver to the duodenum for digestion.
Step-by-step explanation:
The connection between the hepatic diverticulum and the foregut narrows to form a structure known as the bile duct. During embryological development, the hepatic diverticulum gives rise to the liver and its associated structures, such as the bile duct system, which includes the hepatic ducts, cystic duct, and common bile duct. This network of ducts is responsible for the transport of bile, which is essential for the digestion and absorption of fats. This duct is joined by the cystic duct from the gallbladder to form the common bile duct that carries bile into the small intestine, particularly the duodenum.